﻿using System;
using System.Drawing;
using System.Web;

/// <summary>
/// Summary description for validatedCode
/// </summary>
public class ValidatedCode
{
	#region  验证码长度(默认4个验证码的长度)
	int length = 4;
	public int Length
	{
		get { return length; }
		set { length = value; }
	}
	#endregion

	#region 验证码字体大小(为了显示扭曲效果，默认40像素，可以自行修改)
	int fontSize = 40;
	public int FontSize
	{
		get { return fontSize; }
		set { fontSize = value; }
	}
	#endregion

	#region 边框补(默认1像素)
	int padding = 2;
	public int Padding
	{
		get { return padding; }
		set { padding = value; }
	}
	#endregion

	#region 是否输出燥点(默认不输出)
	bool chaos = true;
	public bool Chaos
	{
		get { return chaos; }
		set { chaos = value; }
	}
	#endregion

	#region 输出燥点的颜色(默认灰色)
	Color chaosColor = Color.LightGray;
	public Color ChaosColor
	{
		get { return chaosColor; }
		set { chaosColor = value; }
	}
	#endregion

	#region 自定义背景色(默认白色)
	Color backgroundColor = Color.White;
	public Color BackgroundColor
	{
		get { return backgroundColor; }
		set { backgroundColor = value; }
	}
	#endregion

	#region 自定义随机颜色数组
	Color[] colors = { Color.Black, Color.Red, Color.DarkBlue, Color.Green, Color.Orange, Color.Brown, Color.DarkCyan, Color.Purple };
	public Color[] Colors
	{
		get { return colors; }
		set { colors = value; }
	}
	#endregion

	#region 自定义字体数组
	string[] fonts = { "Arial", "Georgia" };
	public string[] Fonts
	{
		get { return fonts; }
		set { fonts = value; }
	}
	#endregion

	#region 自定义随机码字符串序列(使用逗号分隔)
	string codeSerial = "0,1,2,3,4,5,6,7,8,9";
	public string CodeSerial
	{
		get { return codeSerial; }
		set { codeSerial = value; }
	}
	#endregion

	#region 产生波形滤镜效果
	private const double PI = 3.1415926535897932384626433832795;
	private const double PI2 = 6.283185307179586476925286766559;

	/// <summary>
	/// 正弦曲线Wave扭曲图片（Edit By 51aspx.com）
	/// </summary>
	/// <param name="srcBmp">图片路径</param>
	/// <param name="bXDir">如果扭曲则选择为True</param>
	/// <param name="nMultValue">波形的幅度倍数，越大扭曲的程度越高，一般为3</param>
	/// <param name="dPhase">波形的起始相位，取值区间[0-2*PI)</param>
	/// <returns></returns>
	public System.Drawing.Bitmap TwistImage(Bitmap srcBmp, bool bXDir, double dMultValue, double dPhase)
	{
		System.Drawing.Bitmap destBmp = new Bitmap(srcBmp.Width, srcBmp.Height);

		// 将位图背景填充为白色
		System.Drawing.Graphics graph = System.Drawing.Graphics.FromImage(destBmp);
		graph.FillRectangle(new SolidBrush(System.Drawing.Color.White), 0, 0, destBmp.Width, destBmp.Height);
		graph.Dispose();

		double dBaseAxisLen = bXDir ? (double)destBmp.Height : (double)destBmp.Width;

		for (int i = 0; i < destBmp.Width; i++)
		{
			for (int j = 0; j < destBmp.Height; j++)
			{
				double dx = 0;
				dx = bXDir ? (PI2 * (double)j) / dBaseAxisLen : (PI2 * (double)i) / dBaseAxisLen;
				dx += dPhase;
				double dy = Math.Sin(dx);

				// 取得当前点的颜色
				int nOldX = 0, nOldY = 0;
				nOldX = bXDir ? i + (int)(dy * dMultValue) : i;
				nOldY = bXDir ? j : j + (int)(dy * dMultValue);

				System.Drawing.Color color = srcBmp.GetPixel(i, j);
				if (nOldX >= 0 && nOldX < destBmp.Width
				 && nOldY >= 0 && nOldY < destBmp.Height)
				{
					destBmp.SetPixel(nOldX, nOldY, color);
				}
			}
		}

		return destBmp;
	}
	#endregion

	#region 生成校验码图片
	public Bitmap CreateImageCode(string code)
	{
		int fSize = FontSize;
		int fWidth = fSize + Padding;

		int imageWidth = (int)(code.Length * fWidth) + 4 + Padding * 2;
		int imageHeight = fSize * 2 + Padding;

		System.Drawing.Bitmap image = new System.Drawing.Bitmap(imageWidth, imageHeight);

		Graphics g = Graphics.FromImage(image);

		g.Clear(BackgroundColor);

		Random rand = new Random();

		//给背景添加随机生成的燥点
		if (this.Chaos)
		{

			Pen pen = new Pen(ChaosColor, 0);
			int c = Length * 10;

			for (int i = 0; i < c; i++)
			{
				int x = rand.Next(image.Width);
				int y = rand.Next(image.Height);

				g.DrawRectangle(pen, x, y, 1, 1);
			}
		}

		int left = 0, top = 0, top1 = 1, top2 = 1;

		int n1 = (imageHeight - FontSize - Padding * 2);
		int n2 = n1 / 4;
		top1 = n2;
		top2 = n2 * 2;

		Font f;
		Brush b;

		int cindex, findex;

		//随机字体和颜色的验证码字符
		for (int i = 0; i < code.Length; i++)
		{
			cindex = rand.Next(Colors.Length - 1);
			findex = rand.Next(Fonts.Length - 1);

			f = new System.Drawing.Font(Fonts[findex], fSize, System.Drawing.FontStyle.Bold);
			b = new System.Drawing.SolidBrush(Colors[cindex]);

			if (i % 2 == 1)
			{
				top = top2;
			}
			else
			{
				top = top1;
			}

			left = i * fWidth;

			g.DrawString(code.Substring(i, 1), f, b, left, top);
		}

		//画一个边框 边框颜色为Color.Gainsboro
		g.DrawRectangle(new Pen(Color.Gainsboro, 0), 0, 0, image.Width - 1, image.Height - 1);
		g.Dispose();

		//产生波形（Add By 51aspx.com）
		//image = TwistImage(image, true, 8, 4);

		return image;
	}
	#endregion

	#region 将创建好的图片输出到页面
	public void CreateImageOnPage(string code, HttpContext context)
	{
		System.IO.MemoryStream ms = new System.IO.MemoryStream();
		Bitmap image = this.CreateImageCode(code);

		image.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);

		context.Response.ClearContent();
		context.Response.ContentType = "image/Jpeg";
		context.Response.BinaryWrite(ms.GetBuffer());

		ms.Close();
		ms = null;
		image.Dispose();
		image = null;
	}
	#endregion

	#region 生成随机字符码
	public string CreateVerifyCode(int codeLen)
	{
		if (codeLen == 0)
		{
			codeLen = Length;
		}

		string[] arr = CodeSerial.Split(',');

		string code = "";

		int randValue = -1;

		Random rand = new Random(unchecked((int)DateTime.Now.Ticks));

		for (int i = 0; i < codeLen; i++)
		{
			randValue = rand.Next(0, arr.Length - 1);

			code += arr[randValue];
		}

		return code;
	}
	public string CreateVerifyCode()
	{
		return CreateVerifyCode(0);
	}
	#endregion
}